Background

The United States is not on track to meet the Renewable Fuels Standard targets for advanced biofuels production under the Energy Independence and Security Act of 2007 (Biofuels Interagency Working Group, 2010). Our agricultural and forestry sectors can provide feedstock to support the fledgling industry. However, lack of integration across the entire supply chain has led to sub-optimal solutions and stunted commercial rollout of the advanced biofuels industry.

The goal of this project is to prepare the Pacific Northwest for a 2015 introduction of a 100% infrastructure compatible biofuels industry that meets the region’s share of Renewable Fuels Standard targets using sustainable and regionally appropriate woody energy crops. This will revitalize the region’s forestry industry with establishment of a sustainable advanced biofuels industry that supports large and small growers and brings jobs to rural communities.

Our Work

A suitability analysis for potential to grow poplar was performed over a five state region (Washington, Oregon, California, Idaho, and Montana) using the analytic hierarchy process. First, permanently non-suitable land was removed, including: federal ownership, developed land, steep areas where equipment cannot operate, and areas with high soil salinity. For the remaining land, nine variables considered important for poplar growth were identified: growing season precipitation, temperature, and length; soil texture and drainage, pH, salinity, and depth; water table depth; and slope. Normalizing functions were developed for each variable, and contribution to overall suitability was defined by assigning pairwise importance weights. Normalized values and weights were multiplied together to calculate a final suitability value for each cell. Finally, cells were classified into Highly, Moderately, Marginally or Currently Not Suitable.

We developed two web-based data access applications, one for project partners providing access to the datasets used in our suitability analysis, and a second for examining land suitability for poplar at the parcel level.

The parcel based web app provides suitability scores with and without irrigation for each parcel in the 5 project states, as well as many additional attributes. In support of our project partner, WSU Extension, we also made parcel owner names and addresses available through a secured web app. These names and address can be used as part of outreach programs conducted for education and training events and field trial site visits put on by Extension and Greenwood Resources.

Results

Of the 354 million acres in the region, 188 million acres were identified as permanently non-suitable due to Federal ownership, development, presence of water bodies, steep slopes, or high soil salinity. Without irrigation, 4.4 million acres were classified as highly suitable, with 400 thousand of these acres not classified as agriculture, forestry, disturbed, developed, or water. Irrigation increased the amount of highly suitable acres to 54 million, with 20 million acres not classified agriculture, forestry, disturbed, developed, or water. Growing season precipitation was the most important factor under the "without irrigation" scenario. When irrigation was considered, soil texture and drainage and growing season temperature were the most important factors.